Jung Yun-ho (born February 6, 1986), also known by his stage name U-Know Yunho or simply U-Know, is a South Korean singer, actor, dancer, and a member of the pop duo TVXQ. Born and raised in Gwangju, South Korea, Yunho auditioned for the Korean talent agency S.M. Entertainment in 2001. After over two years of training, Yunho debuted with TVXQ in December 2003.